The effect of prolonged repetitive stimulation with either 60 or 90 dB tones is examined in chronic schizophrenics, normals, and non-schizophrenic psychiatric patients. EEG recordings are made from left and right temporal and occipital leads: electrodermal and finger pulse volume recordings from each hand. We wish to determine whether our previous reports of schizophrenic hypofunction consisting of either nonresponsiveness or abrupt, rapid habituation of response can be confirmed; whether this will generalize across autonomic measures and include CNS as well as ANS response; whether dysfunction is greater in one (left) hemisphere/hand, and greater in temporal than occipital leads; whether schizophrenic or habituation is relatively unstable, showing a greater and more rapid resurgence following initial habituation, and whether this is associated with evidence of increased cortical inhibition and subcortical released in these patients, or with heightened internally generated "arousal".